CT assessment of tracheobronchial anomaly in left pulmonary artery sling

Bridge bronchus and pulmonary artery sling: Case report and literature review

We present the case of a 14-year-old adolescent boy with a history of poorly controlled asthma and a final diagnosis of a bridge bronchus associated with sling of the left pulmonary artery. Regarding the case report, we describe the characteristic findings in computerized tomography multidetector of the thorax, its classification, and the most relevant information about this malformation. Congenital malformations of the tracheobronchial tree may occur in the context of asymptomatic or symptomatic respiratory patients. These malformations may be associated with other vascular, tracheal, and syndromes with multiorgan involvement. Although most patients are asymptomatic, some of them will have nonspecific symptoms without a clear etiology or will be diagnosed incidentally during the diagnostic evaluation of other pathologies. It is important to know and recognize the normal anatomy and its variations, since radiology undoubtedly plays a fundamental role in the diagnosis and preoperative assessment of these malformations, which although they have low incidence, must be identified in a timely manner by the specialist in diagnostic images.

A rare duo: Pulmonary arterial sling with a pig bronchus

Pulmonary artery sling is an incomplete vascular ring, where the left pulmonary artery originates from the right pulmonary artery, leading to airway constriction. A tracheal bronchus is an anatomical variation in which an extra bronchus originates from the trachea, frequently resulting in respiratory symptoms or complications. We report a 6-week-old female patient with a pulmonary artery sling coursing around the distal trachea and a concurrent tracheal bronchus.

Pediatric Cardiovascular Computed Tomography: Clinical Indications, Technique, and Standardized Reporting. Recommendations From the Cardiothoracic Taskforce of the European Society of Pediatric Radiology

Congenital heart diseases affect 1% of all live births in the general population. The prognosis of these children is increasingly improving due to advances in medical care and surgical treatment. Imaging is also evolving rapidly to assess accurately complex cardiac anomalies prenatally and postnatally. Transthoracic echocardiography is the gold-standard imaging technique to diagnose and follow-up children with congenital heart disease. Cardiac computed tomography imaging plays a key role in the diagnosis of children with congenital heart defects that require intervention, due to its high temporal and spatial resolution, with low radiation doses. It is challenging for radiologists, not primarily specialized in this field, to perform and interpret these studies due to the difficult anatomy, physiology, and postsurgical changes. Technical challenges consist of necessary electrocardiogram gating and contrast bolus timing to obtain an optimal examination. This article aims to define indications for pediatric cardiac computed tomography, to explain how to perform and report these studies, and to discuss future applications of this technique.

Pulmonary artery sling: An overview

Pulmonary artery sling is a rare childhood vascular tracheobronchial compression syndrome that is frequently associated with tracheal stenosis. Consequently, neonates or infants may present with critical airway obstruction if there is long segment airway narrowing and complete rings. Rapid diagnosis of this cardiac vascular malformation and evaluation of the extent and severity of airway involvement is essential to plan surgery, typically a slide tracheoplasty to relieve critical airway obstruction. Long term outcome can be excellent following surgical repair of the stenosed airway and reimplantation of the left pulmonary artery. In this review we focus on the embryology, diagnostic workup, airway investigations and management for this rare but challenging congenital condition.

Lung volume determination by dual-source computed tomography in infants with pulmonary artery sling: a case-control study

BACKGROUND

Pulmonary artery sling (PAS) is associated with tracheal stenosis and left pulmonary artery (LPA) dysplasia in infants, both developmental abnormalities that may lead to pulmonary hypoplasia and lung volume changes. As such, we aimed to monitor the effects of tracheal stenosis and pulmonary vascular malformation on lung volumes in infants with PAS and their correlation with lung volumes in infants with PAS using dual-source computed tomography (DSCT).

METHODS

A case-control study was performed. From May 2009 to June 2017, we retrospectively enrolled patients with surgically confirmed PAS and compared them to matched normal controls (A healthy control group comprising age- and gender-matched patients with adequate imaging data was used for the comparisons.). All the patients underwent DSCT examinations. We measured and compared the diameters of the trachea, main bronchus, and main pulmonary artery (MPA) and its branches, and both lung volumes on the axial, and reconstructed CT images.

RESULTS

There were no statistical differences in the diameters of the MPA or right pulmonary artery (RPA) between patients (N=15) and controls (N=28). The diameter of the main bronchus, the bilateral trachea and the left pulmonary artery were all smaller in the PAS group than in the control group, and significant differences were evident in the left lung volume the right lung volume, and the right-to-left lung volume ratio between the 2 groups. Pearson's correlation and linear regression analyses between the diameters of the trachea and MPA, total lung volume, ipsilateral bronchial and pulmonary artery branches, and ipsilateral lung volume ranged from 0.71 to 0.87 and 0.57 to 0.77 for the control and PAS groups, respectively.

CONCLUSIONS

Tracheal stenosis and LPA dysplasia in infants with PAS cause alterations in lung tissue morphology and physiological development, resulting in reduced bilateral lung volumes.

Left Pulmonary Artery Sling: Postoperative Outcomes for Patients at a Single Center

BACKGROUND

Left pulmonary artery (LPA) sling is a rare anomaly characterized by the origin of the LPA from the right pulmonary artery with a course between the trachea and esophagus. It is often associated with airway and cardiac anomalies.

METHODS

This is a retrospective case series of consecutive patients who underwent LPA sling repair (LPASR) at a tertiary care center over a 35-year period with a focus on tracheal and/or LPA reinterventions and survival.

RESULTS

Between June 1983 and July 2018, 42 patients were identified: isolated LPASR was performed in 16 (38%), LPASR/intracardiac repair in 10 (24%), and LPASR/tracheal repair in 16 (38%). There were 5 (12%) in-hospital and 4 (10%) late deaths. Survival rates (15 years) were as follows: 100% (isolated LPASR), 65% (concomitant intracardiac repair), and 52% (concomitant tracheal surgery). Preoperative intensive care unit (ICU) hospitalization was associated with future intervention on the LPA/trachea (61%, 11/18). The median distribution of blood flow to the left lung post-index surgery was 38%. Freedom from isolated LPA intervention was 100% after isolated LPASR, 93% after LPASR/tracheal surgery, and 69% after LPASR/intracardiac repair. Freedom from isolated tracheal intervention was 92% after isolated LPASR, 73% after LPASR/tracheal surgery, and 78% after LPASR/intracardiac repair.

CONCLUSIONS

ICU hospitalization prior to index surgery may indicate the severity of associated cardiac/tracheal abnormalities as this is associated with increased morbidity and mortality. Patients who underwent LPASR/intracardiac surgery were more likely to undergo isolated LPA intervention and those who underwent LPASR/tracheal surgery were more likely to undergo isolated tracheal intervention.

Pediatric Cardiothoracic CT Guideline Provided by the Asian Society of Cardiovascular Imaging Congenital Heart Disease Study Group: Part 2. Contemporary Clinical Applications

The use of pediatric cardiothoracic CT for congenital heart disease (CHD) was traditionally limited to the morphologic evaluation of the extracardiac thoracic vessels, lungs, and airways. Currently, the applications of CT have increased, owing to technological advancements in hardware and software as well as several dose-reduction measures. In the previously published part 1 of the guideline by the Asian Society of Cardiovascular Imaging Congenital Heart Disease Study Group, we reviewed the prerequisite technical knowledge for clinical applications in a user-friendly and vendor-specific manner. Herein, we present the second part of our guideline on contemporary clinical applications of pediatric cardiothoracic CT for CHD based on the consensus of experts from the Asian Society of Cardiovascular Imaging CHD Study Group. This guideline describes up-to-date clinical applications effectively in a systematic fashion.

Surgery for right upper lobe lung cancer in a patient with bridging bronchus

A 70-year-old man with back pain presented with a tumor invading the chest wall of his right upper lobe. Three-dimensional computed tomography revealed an aberrant right lower bronchus originating from the left main bronchus. Open thoracotomy right upper lobectomy with combined resection of the chest wall was performed under ventilation for the left and right lower lobes. The aberrant bronchus was defined as a bridging bronchus, a rare congenital anomaly. For such cases, careful planning is necessary to manage ventilation during operation. The area and extent of lymph node dissection are debatable.

Prenatal diagnosis and postnatal course in four fetuses with very rare pulmonary artery anomalies

Pulmonary artery (PA) anomalies are very rare congenital cardiac malformations, a significant number of which remain unrecognized or misdiagnosed during the prenatal period. We report the prenatal diagnosis and outcome of pregnancy with fetal PA anomalies and discuss the related management issues. We identified four cases of prenatally diagnosed rare PA anomalies that were seen and confirmed in the newborn period by echocardiography and computed tomographic angiography at our center from 2018 to 2020. The course of the pregnancy, perinatal outcome, and the postnatal course in each case were analyzed. Three fetuses were born by repeat cesarean section approximately at 39 weeks of gestation and the other woman delivered vaginally. Of the abnormal origin of the left PA (LPA) in two patients, the first had right PA abnormalities derivating from the ascending aorta, and in the second, the LPA originated from the right PA. Two patients had agenesis of ductus arteriosus (DA), the first was accompanied with tetralogy of Fallot (TOF) and right aortic arch with a normal pulmonary valve, the second patient presented with an Absent Pulmonary Valve syndrome with TOF. Prenatal ultrasonography can be used to correctly diagnose the abnormal origin of the PA branches. Branching of the PA, presence of DA, location of the aortic, and ductal arch by the trachea should be routinely screened in the prenatal anatomic examination and the three-vessel and trachea view can determine the primary clues of PA malformations.

Midterm outcomes of pulmonary artery sling repair with and without tracheoplasty

OBJECTIVE

Review a single-centre experience with pulmonary artery sling repair and evaluate risk factors for re-intervention.

METHODS

Patients with surgically repaired pulmonary artery sling at a single institution between 1996 and 2018 were retrospectively reviewed. A univariate Cox regression analysis was used to evaluate variables for association with freedom from re-intervention.

RESULTS

Eighteen patients had pulmonary artery sling repair. At operation, median age and weight were 6.9 months (interquartile range 4.1-18.1) and 9.5 kg (interquartile range 6.5-14.5), respectively. A median hospital length of stay was 12 days (interquartile range 5.8-55.3). Twelve patients (67%) had complete tracheal rings, of whom six (50%) underwent tracheoplasty (five concurrently with pulmonary artery sling repair). Airway re-intervention was required in five (83%) of the six patients who underwent tracheoplasty. One patient had intraoperative diagnosis and repair of pulmonary artery sling during unrelated lesion repair and required tracheoplasty 24 days post-operatively. One patient died 55 days after pulmonary artery sling repair and tracheoplasty following multiple arrests and re-interventions. Median post-operative follow-up for surviving patients was 6.3 years (interquartile range 11 months-13 years), at which time freedom from re-intervention was 61%. When controlling for patient and tracheal size, initial tracheoplasty was associated with decreased freedom from re-intervention (hazard ratio 21.9, 95% confidence interval 1.7-284.3, p = 0.018).

CONCLUSIONS

In patients with pulmonary artery sling, tracheoplasty is associated with decreased freedom from re-intervention. In select patients with pulmonary artery sling and complete tracheal rings, conservative management without tracheoplasty is feasible. Further study is necessary to delineate objective indications for tracheoplasty.

Pulmonary sling in a patient with common arterial trunk

We report a rare association of common arterial trunk with left pulmonary artery sling and highlight the importance of cross-sectional imaging in complex congenital cardiac lesions. The patient was antenatally diagnosed with common arterial trunk and underwent surgical repair in the neonatal period. At the age of 20 months, the patient presented with respiratory symptoms and increased right ventricular pressure. Multislice computed tomography demonstrated a pulmonary sling with compression of the distal trachea. Surgical correction of the pulmonary sling and change of the right ventricular to pulmonary artery conduit to a bigger size was performed.

Tracheoplasty for Patients with Pulmonary Artery Sling and Tracheal Stenosis: A Meta-Analysis

We performed this meta-analysis to assess the safety and efficacy of tracheoplasty for patients with pulmonary artery sling (PAS) and tracheal stenosis. Published studies that included surgical treatment of PAS and tracheal stenosis with and without tracheoplasty were identified by searching the PubMed, EMBASE, and Cochrane Library databases until May 2020. The outcomes assessed included postoperative ventilation time, early and late mortality, and follow-up respiratory symptoms. The mean difference (MD)/risk ratio (RR) with 95% confidence intervals (CI) was estimated with a random-effects/fixed-effects model. Subgroup analysis was performed stratified by percentage of patients with tracheal rings. A total of eight studies comprising 219 patients with PAS accompanied by tracheal stenosis were included. The pooled estimates of postoperative ventilation time (MD 17.68, 95% CI 6.38 to 28.98, p < 0.01) and early mortality (RR 3.93, 95% CI 1.55 to 9.95, p < 0.01) favored the repair-only group. Late mortality (RR 1.33, 95% CI 0.48 to 3.68, p = 0.58) and respiratory symptoms (RR 1.51, 95% CI 0.50 to 4.57, p = 0.47) at follow-up showed no significant differences between the groups with repair-only and repair with tracheoplasty. The same results were found in subgroup analyses. For the surgical treatment of PAS with tracheal stenosis, repair without tracheoplasty appears to result in shorter postoperative ventilation time and lower early mortality, with no increase in late mortality or respiratory symptoms at follow-up, compared with concomitant tracheoplasty.

Incidental finding of an aberrant left pulmonary artery, an aberrant right subclavian artery, and a tracheal bronchus in an adult woman with a meningioma and a history of medulloblastoma

The aberrant left pulmonary artery and the aberrant right subclavian artery are rare congenital vascular anomalies, and the tracheal bronchus is a rare congenital respiratory anomaly. A 33-year-old female patient, with a history of desmoplastic medulloblastoma, was surgically treated at our hospital for a meningioma. On the second postoperative day, the patient complained of shortness of breath and chest pain. Contrast-enhanced multislice computed tomography was negative for pulmonary embolism, but incidentally revealed all three congenital anomalies. In our report, we detail this exceedingly rare case.

Esophagectomy for Esophageal Cancer in a Patient with Left Pulmonary Artery Sling

BACKGROUND

In esophageal squamous cell cancer (ESCC) patients, the dissection of the lymph nodes around the recurrent laryngeal nerve (RLN) is essential for curative esophagectomy.1,2 Left pulmonary artery sling (LPAS) is a rare congenital anomaly, in which anomalous left pulmonary artery arises from the right pulmonary artery and reach the left pulmonary hilum.3-5 Because LPAS crosses between esophagus and trachea and the hemodynamics of LPAS could collapse when retracting the trachea anteriorly for left RLN node dissection, esophagectomy for patients with LPAS is technically challenging. In this video, we applied the cervicothoracoscopic approach in a patient with LPAS, in which we performed bilateral RLN node dissection from cervical operation field before thoracoscopic surgery.6,7 METHODS: A 44-year-old woman was diagnosed with stage II ESCC. Following neoadjuvant chemotherapy, we planned to perform a three-stage esophagectomy. Preoperative-enhanced computed tomography revealed LPAS. During the cervical procedure, we identified the RLN, dissected the lymph nodes around the nerve, and mobilized the cervical esophagus. After the cervical procedures, we performed thoracoscopic surgery through the right thoracic cavity with the patient in a prone position.

RESULTS

We achieved curative esophagectomy without any intraoperative adverse events. Total operation time was 419 min, with an estimated blood loss of 40 ml. There were no postsurgical complications, including RLN palsy.

CONCLUSIONS

The presence of LPAS in esophageal cancer surgery makes it difficult to dissect the left RLN nodes. We could safely perform curative esophagectomy for an ESCC patient with LPAS using the cervicothoracoscopic approach.

Cross-sectional imaging of congenital pulmonary artery anomalies

Congenital pulmonary artery (PA) anomalies comprise a rare and heterogeneous spectrum of disease, ranging from abnormal origins to complete atresia. They may present in early infancy or more insidiously in adulthood, often in association with congenital heart disease such as tetralogy of Fallot or other syndromes. In recent years, cross-sectional imaging, including computed tomography (CT) and magnetic resonance imaging (MRI), has become widely utilized for the noninvasive assessment of congenital PA diseases, supplementing echocardiography and at times supplanting invasive angiography. In this article, modern CT and MRI techniques for imaging congenital PA disorders are summarized. The key clinical features, cross-sectional imaging findings, and treatment options for the most commonly encountered entities are then reviewed. Emphasis is placed on the ever-growing role of cross-sectional imaging options in facilitating early and accurate diagnosis and tailored treatment.

Long-term outcomes of surgery for pulmonary artery sling in children

OBJECTIVES

Pulmonary artery (PA) sling is a rare vascular anomaly often associated with congenital tracheal stenosis. We describe the long-term outcomes with repair of this condition.

METHODS

A retrospective study was conducted at 2 institutions. From 1984 to 2018, 33 patients with PA sling underwent repair.

RESULTS

The median age at the time of surgery was 5.9 months (quartile 1-3: 2.5-12 months). Concomitant tracheal surgery was required in 21 patients (64%) where slide tracheoplasty was used in 11 patients (52%). There were no early deaths in patients who did not require tracheal surgery (n = 12). Operative mortality was 22% (2 of 9 patients) between 1984 and 1993, 11% (1 of 9 patients) between 1994 and 2003 and 6.7% (1 of 15 patients) between 2004 and 2018. The 15-year probability of survival for patients who had PA sling repair alone was 100%, and for patients who required PA sling and tracheal repair was 76 ± 10% (95% confidence interval 51-89%) (P = 0.08). The mean follow-up for survivors was 14 ± 9.8 years (3 months-33 years). All survivors were in the New York Heart Association functional class I/II at the last follow-up. Spirometry performed at a median age of 10.4 years after PA sling and tracheal surgery demonstrated obstructive lung defects with median forced expiratory volume in 1 s of 1.0 l (48% predicted), forced vital capacity of 1.5 l (74% predicted) and forced expiratory volume in 1 s/forced vital capacity of 0.69 (78% predicted).

CONCLUSIONS

Early mortality after PA sling repair is determined by the need for tracheal surgery. Though late survival was excellent, and the majority of survivors remained asymptomatic, long-term respiratory assessment and follow-up is warranted for these patients.

Clinical and imaging features of pulmonary artery sling: The experience in one major medical center

This case series describes echocardiographic and computed tomography angiographic (CTA) characteristics, clinical features, diagnosis, and treatment in 15 patients of Pulmonary artery sling (PAS). Echocardiography is effective in diagnosing PAS, when the main pulmonary artery extends to the right pulmonary artery directly with the left pulmonary artery arising from the right pulmonary artery. CTA, clearly demonstrating the position and extent of trachea compression, the anatomy of PAS and the spatial relationships among the PAS, trachea and the esophagus, is necessary for the final diagnosis. Clinical presentations are caused by the compression of the tracheobronchial tree rather than the PAS itself. Left pulmonary artery reimplantation is the treatment of choice.

Prenatal diagnosis of anomalous origin of pulmonary artery

BACKGROUND

Anomalous origin of the pulmonary arteries is a rare congenital pulmonary vascular malformation that includes unilateral absence of the pulmonary artery (UAPA), anomalous origin of unilateral pulmonary artery (AOPA), and left pulmonary artery sling (LPAS).

METHODS

We analyze 15 cases of fetal pulmonary artery abnormalities from 2011 to 2017, detected via prenatal ultrasound at our center.

RESULTS

The 15 cases include UAPA (5), AOPA (6), and LPAS (4). Of the UAPA cases, 2 had pulmonary atresia and 3 had pulmonary artery stenosis. In 5 cases, the descending aorta issued collateral vessels to the left lung. Of the AOPA cases, 2 had left pulmonary artery abnormalities originating in the ascending aorta and 4 showed right pulmonary artery abnormalities originating in the ascending aorta. Of the LPAS cases, 2 were type IA, 1 was type IIA, and 1 was type IIB. Two of the LPAS were associated with right lung dysplasia.

CONCLUSION

Abnormal origin of the pulmonary artery has a characteristic ultrasonographic appearance. The branch of the pulmonary artery cross section can provide important clues to the diagnosis of abnormal pulmonary artery origin. Pulmonary artery abnormalities are often associated with pulmonary atresia or stenosis.

New Directions in 3D Medical Modeling: 3D-Printing Anatomy and Functions in Neurosurgical Planning

This paper illustrates the feasibility and utility of combining cranial anatomy and brain function on the same 3D-printed model, as evidenced by a neurosurgical planning case study of a 29-year-old female patient with a low-grade frontal-lobe glioma. We herein report the rapid prototyping methodology utilized in conjunction with surgical navigation to prepare and plan a complex neurosurgery. The method introduced here combines CT and MRI images with DTI tractography, while using various image segmentation protocols to 3D model the skull base, tumor, and five eloquent fiber tracts. This 3D model is rapid-prototyped and coregistered with patient images and a reported surgical navigation system, establishing a clear link between the printed model and surgical navigation. This methodology highlights the potential for advanced neurosurgical preparation, which can begin before the patient enters the operation theatre. Moreover, the work presented here demonstrates the workflow developed at the National University Hospital of Iceland, Landspitali, focusing on the processes of anatomy segmentation, fiber tract extrapolation, MRI/CT registration, and 3D printing. Furthermore, we present a qualitative and quantitative assessment for fiber tract generation in a case study where these processes are applied in the preparation of brain tumor resection surgery.

Sling Pulmonary Artery with Bridging Bronchus and Narrowing Airway: A Case Report

We present a case of a 10-month-old girl baby with pulmonary artery sling and bridging bronchus demonstrated using multidetector computed tomography with a three-dimensional volume-rendering display and minimum intensity projections. To the best of our knowledge, this method has been helpful not only in the diagnosis and surgical planning for this rare abnormality but also in the evaluation of prognosis. After pulmonary artery reimplantation, the patient was well and discharged.

Evaluation of left pulmonary artery sling, associated cardiovascular anomalies, and surgical outcomes using cardiovascular computed tomography angiography

We evaluated the prevalence, image appearance, associated cardiovascular anomalies, and surgical outcomes of left pulmonary artery sling (LPAS) using cardiovascular computed tomography angiography (CCTA). A retrospective search of patients from our database between October 2007 and December 2014 identified 52,200 patients with congenital heart diseases (CHD) referred for CCTA, echocardiography, or magnetic resonance imaging. Clinical information, CCTA findings, associated cardiovascular anomalies, and surgical outcomes were analyzed. We showed a hospital-based prevalence of 71 patients with LPAS (0.14%, 71/52,200) among CHD patients. Of these, 47 patients with CCTA examinations were assessed further. Most patients (40/47, 85%) had associated cardiovascular anomalies, of which ventricular septal defects (22/47, 47%), atrial septal defects (20/47, 43%), patent ductus arteriosus (16/47, 34%), persistent left superior vena cava (14/47, 30%), and abnormal branching of the right pulmonary artery (ABRPA) (14/47, 30%) were most commonly identified. In total, 28 patients underwent LPA reanastomosis and/or tracheoplasty in our center, and 5 died. LPAS had a hospital-based prevalence of 0.14% among CHD patients. ABRPA is not uncommon and must be recognized. CCTA is a feasible method for demonstrating LPAS and its associated cardiovascular anomalies for an optimal pre-operative assessment of LPAS.

Tracheobronchial Branching Abnormalities: Lobe-based Classification Scheme

Boyden's nomenclature, which was based on postmortem specimens and published in 1955 prior to the advent of computed tomography (CT), is commonly used to describe the normal segmental bronchial anatomy and various abnormalities. However, several additional anomalies have been recognized since that time, and there is some confusion over the names used to describe these anomalies. Several congenital branching anomalies affecting the trachea, main bronchi, and intermediate bronchus have been reported, all of which can be recognized at chest CT but are often overlooked. These anomalies, which probably occur early in fetal life, can be either supernumerary, with defects occurring at 29-30 days gestation, or displaced, with defects occurring later. Tracheobronchial positional anomalies are often associated with other congenital abnormalities but may be isolated. They often are asymptomatic but can be responsible for pulmonary symptoms such as dyspnea, recurrent pneumonia, and hemoptysis. It is essential that these anomalies are recognized prior to lung resection to avoid complications, especially when video-assisted thoracoscopic surgery is performed. In addition, bronchoscopists should be aware of these anomalies before performing diagnostic or therapeutic bronchoscopic procedures. Awareness of a few key bronchial anatomic principles and use of a lobe-based classification scheme will facilitate recognition of tracheobronchial positional anomalies.

Imaging modalities in children with vascular ring and pulmonary artery sling

PURPOSE

Our aim is to compare new non-invasive imaging modalities in the evaluation of vascular ring (VR) and pulmonary artery sling (PAS) and to understand the role of bronchoscopy in comparison with them in assessing tracheobronchial tree.

METHODS

We have retrospectively analyzed the data from 41 patients with a VR or a PAS diagnosed at Bambino Gesù Children's Hospital of Rome, between 2008 and 2012. Age, gender, presenting symptoms, clinical history, comorbidities, imaging modalities used for diagnosis (cardiac magnetic resonance [CMR], computed tomography [CT], tracheobronchoscopy [TB]) and surgical treatment were recorded.

RESULTS

The vascular anatomy was completely defined in all patients, whether evaluated by CMR or CT, with a diagnostic accuracy of 100% based on surgical observation. All CT exams were performed without sedation with a mean dose-length product (DLP32 ) of 29 ± 9 and an effective dose of 1.56 ± 0.6 mSv, range 0.5-2.5 mSv. CMR required general anesthesia in all patients but involved no exposure to ionizing radiation. CT performed better than CMR in assessing tracheal stenosis when compared to TB. It detected complete tracheal cartilage rings in 2/3 patients with PAS, besides tracheomalacia and/or bronchomalacia in 54% of patients.

CONCLUSIONS

Both cross-sectional imaging modalities (CT and CMR) can reliably and accurately diagnose these congenital vascular anomalies. While CT involves exposure to ionizing radiation, it avoids the risks related to anesthesia needed for CMR, and provides a more accurate assessment of tracheobronchial anatomy. TB remains a fundamental tool in tracheomalacia diagnosis in VR symptomatic patients and PAS.

Bridging bronchus: Importance of recognition on airway endoscopy

Bridging bronchus is an anomalous bronchus, which crosses the mediastinum from the contralateral mainstem bronchus and it is commonly associated with congenital great vessel abnormalities. This is a case report of an infant that underwent airway endoscopy and attempt at cannulation of a mainstem bronchus with supposed bronchial cast after cardiac surgery in the intensive care unit. After multiple failed attempts, further workup was completed which revealed a bridging bronchus. A bridging bronchus must be suspected in a patient with abnormal appearing endoscopy in presence of great vessel anomalies to prevent accidental injury to the tracheobronchial tree.

Sling left pulmonary artery with patent type IIA tracheobronchial anomaly and imperforate anus

We present a 3-month-old boy with a type IIA sling left pulmonary artery associated with imperforate anus and rectourethral fistula. Tracheobronchial abnormalities are demonstrated using multidetector CT with 3-D volume rendering of the airways. This case represents a novel variant of an already rare entity with an unusually high right upper lobe bronchus and no evidence of associated tracheobronchial stenosis.

Multi-slice computed tomography assessment of bronchial compression with absent pulmonary valve

BACKGROUND

Absent pulmonary valve is a rare cardiovascular anomaly that can result in profound tracheobronchial compression.

OBJECTIVE

To demonstrate the advantage of multi-slice CT in diagnosing tracheobronchial compression, its severity as related to the adjacent dilated pulmonary arteries, and associated lung and cardiac lesions.

MATERIALS AND METHODS

We included children with absent pulmonary valve who were reviewed by multi-slice CT during a 17-year period. The number and locations of stenoses and lung lesions were noted and the severity of stenosis was categorized. The diameter of the pulmonary artery was measured and associated cardiac defects were demonstrated.

RESULTS

Thirty-one children (14 girls and 17 boys) were included. Of these, 29 had ventricular septal defect and 2 had an intact ventricular septum. Twenty-nine children (94%) had tracheobronchial compression, judged to be mild in nine children (31%), moderate in 10 (34%) and severe in 10 (34%). The different locations of the stenosis (carina, main bronchi, lobar and segmental bronchi) were observed. And the number and location of lung lesions demonstrated that the right middle and left upper and lower lobes were often affected. The diameter of the pulmonary artery in these children was well above normal published values, and Spearman rank correlation analysis showed a correlation between the size of the pulmonary artery and the severity of the tracheobronchial stenosis. Nineteen children (61%) underwent surgery and 4 of these children had a multi-slice CT post-operative follow-up study.

CONCLUSION

Absent pulmonary valve can cause significant morbidity and mortality in children. Multi-slice CT can accurately depict areas of tracheobronchial compression, associated lung lesions and cardiac defects, helping to direct the surgeon.

Three-dimensional printing model of anomalous bronchi before surgery

Lung surgeries in patients with bronchial variations have rarely been reported. Here, we describe the case of a patient along with lung cancer with variant anatomy of the right upper lobe bronchus. This variation was evaluated by three-dimensional multi-detector computed tomography angiography with bronchography and a three-dimensional printing model using rapid prototyping. The variant anterior segment bronchus (S3) of the right upper lobe arising from the middle lobe bronchus was confirmed before surgery using the printing model, which helped to determine the extent of resection required and facilitated the understanding of the patient's anatomy during surgery. A thoracoscopic anterior segmentectomy and middle lobectomy were performed. The printing model was useful for detecting and evaluating the variant bronchi.

Computed tomography guided thoracoscopic segmentectomy for lung cancer with variant bronchus

Lung segmentectomy with bronchial variation has rarely been reported. We report the case of a lung cancer patient with variant anatomy of the right upper lobe bronchus.Thoracoscopic posterior segmentectomy of the right upper lobe was performed. Variant bronchus and related blood vessels were confirmed preoperatively by three-dimensional multidetector computed tomography (3D-MDCT), which facilitated visualization of the patient's anatomy during surgery.

Surgical management of pulmonary artery sling in children

OBJECTIVES

Pulmonary artery (PA) sling is a rare vascular anomaly associated with congenital tracheal stenosis. The natural history is poor and these patients often require early surgical intervention. We describe our experience with repair of this condition.

METHODS

From 1984 to 2011, 21 patients with PA sling underwent repair at the Royal Children's Hospital (median age, 5.9 months). PA sling was associated with compression of the trachea in all patients. Tracheal surgery was required in 12 (57.1%) patients. All patients had an echocardiogram, and concomitant repair of coexisting cardiac anomalies was performed in 6 (28.6%, 6/21) patients.

RESULTS

Operative mortality was 14.3% (3/21), occurring at 19 days, 4.4 months, and 5 months after surgery. Operative mortality for the first 10 years was 22.2% (1984-1993; 2/9), the next 10 years was 14.3% (1994-2003; 1/7), and 0% for the most recent 7 years (2004-2011; 0/5). All deaths occurred in patients requiring tracheal repair (25%, 3/12). No deaths have occurred since 2004 with introduction of the slide tracheoplasty technique. One (5.6%, 1/18) late death occurred at 8 months after repair. After tracheal repair, intervention for excessive granulations and tracheomalacia was necessary in 6 (50%, 6/12) patients. Median follow-up was 8 years (mean, 8.6 ± 6.4 years; range, 5 months to 20.6 years), and all survivors (100%, 17/17) remain asymptomatic.

CONCLUSIONS

Children with PA sling who do not require tracheal surgery have excellent outcomes. Mortality is determined by the need for tracheal surgery. However, with the advent of the slide tracheoplasty technique, mortality can be reduced. Survival beyond 1 year after surgery offers excellent prognosis.

The triad of bridging bronchus malformation associated with left pulmonary artery sling and narrowing of the airway: the legacy of Wells and Landing

Although noted in the 19th century, it was not until 1938 that Scheid published the combination of left pulmonary artery sling and narrowing of the airway due to annular tracheal cartilages. Unaware of these prior descriptions, and without a precise preoperative diagnosis, Willis Potts in Chicago performed the first successful sling repair in 1953. In 1976, Cohen and Landing described Scheid's combination of left pulmonary artery sling and stenosis caused by complete tracheal rings, and the term "ring-sling complex" was introduced by Berdon in 1984. Four years later, Wells and Landing noted characteristic tracheobronchial malformations associated with these lesions and proposed a classification that has been confirmed to be clinically relevant in recent cross-sectional imaging studies.

Common and uncommon vascular rings and slings: a multi-modality review

Vascular rings and pulmonary slings are congenital anomalies of the aortic arch/great vessels and pulmonary arteries, respectively, that commonly present early during infancy and childhood with respiratory and/or feeding difficulties. The diagnosis of these conditions frequently utilizes a multi-modality radiological approach, commonly utilizing some combination of radiography, esophagography, CT angiography and MR angiography. The purpose of this pictorial review is to illustrate the radiological findings of common and uncommon vascular rings and pulmonary slings in children using a state-of-the-art multi-modality imaging approach.

Imperforate anus, diaphragmatic hernia, horseshoe kidney, and pulmonary sling complex: case description

This report describes an infant with imperforate anus, delayed presentation of congenital diaphragmatic hernia, horseshoe kidney, and pulmonary sling complex, a unique combination of anomalies that we recently treated at our facility.